Our proposal, Human Immunology Project Consortium (DHIPC), is based on an innovative strategy, compelling preliminary studies, and a wide network of multidisciplinary collaborations and will study the human immune responses 1) during or following dengue virus (DENV) infection, 2) before and after live attenuated DENV vaccination, using high-throughput systems biology approaches coupled with detailed clinical phenotyping in well-characterized human cohorts. The long-term goal is to develop molecular signatures that define immune response and categories/fingerprints/profiles that correlate with the outcome of infection and vaccination. We will use omics technology platforms including genomics (Core B), RNAi screens (Project 3) and proteomics (Core C), and immune profiling (Core D) to study human cells from healthy donors (Project 3) and well characterized human cohorts of DENV infected children that include symptomatic versus non-symptomatic infections in dengue endemic areas (Project 1). We also include studies of live attenuated DENV vaccinations in humans (Project 2), to predict immunogenicity, and in the future correlate immune profiles determined before or soon after vaccination with protective efficacy, and also with adverse events triggered by vaccination. The data analysis and modeling core (Core E) will be the engine for translating omics data into biological insight and the data Management Dissemination Core (Core F) will act as a central repository for all data and resources generated by the Center, and ensure that these materials are readily accessible by not only other scientists in the program, but also the broader scientific community. The results of our proposed systems immunology studies will create a foundation for future hypothesis-driven research and may help develop diagnostic tools and define immune profiles correlated with outcomes of infection and vaccination. The Projects and Cores are overseen by an Administrative Core (Core A), which has an organizational structure for reporting and accountability to maintain scientific and fiscal flexibility and responsibility. Dengue disease is of great public health importance and our program has the unique opportunity to compare natural infections with live attenuated vaccines under clinical development both in vivo and ex vivo, building a new paradigm for studying other human infectious diseases in the settings of infection and vaccination. Project-001: Project 1 - Immune Profiling of Natural Dengue Virus Infections Project Leader (PL): Eva Harris DESCRIPTION (as provided by applicant): The four dengue virus serotypes (DENV1-4) cause the most important mosquito-borne viral disease of humans, with ~100 million cases annually, yet no approved vaccines or antivirals exist. Factors that determine disease outcome following DENV infection are not well understood and are thought to be mediated in part by host immune responses. Viral factors and host innate immune interactions likely influence the quality of the adaptive immune response, which can either protection provide or cause enhancement in a subsequent DENV infection. Project 1 of the Dengue Human Immunology Project Consortium (DHIPC) focuses on characterizing immune signatures associated with infection outcomes and disease severity in natural DENV infections. The overall approach of Project 1 is to take advantage of unique sample sets from long-term ongoing studies of dengue in Nicaragua to enable discovery of immune factors associated with symptomatic DENV infection, severe dengue disease, and specific adaptive immune responses. Project 1 will continue the Nicaraguan Pediatric Dengue Cohort Study (PDCS) to collect samples from well-documented natural repeat DENV infections. It will also leverage an on-going hospital-based study of dengue in Nicaragua to enable investigation of severe vs. mild dengue disease and will conduct an index cluster study to provide samples from asymptomatic viremic individuals. Detailed clinical data will accompany all samples. In conjunction with the world-class DHIPC Cores, a systems biology approach will be used to construct a signature of innate immune responses during natural DENV infection. The constellation of complementary cutting-edge genomic, transcriptomic, proteomic, seromic, and immunophenotyping methods will enable the human immune response to dengue to be dissected with unprecedented detail and sophistication. Aim 1 will characterize immune profiles in DENV infections with different clinical outcomes: asymptomatic and symptomatic DENV infection using the index cluster study and mild vs. severe disease in the PDCS and the hospital-based study. Aim 2 will characterize immune profiles in primary and secondary DENV infections, in specific serotype order of infection. Aim 3 will investigate the association between innate immune signatures and antibody and cell-mediated immune responses. Antibody neutralization, isotype, and repertoire will be evaluated, as well as the magnitude and serotype-specificity or cross-reactivity of the B cell response within Project 1. T cell responses will be evaluated for multi-functionality by intracellular cytokne staining. Overall, Project 1 will enable identification of biomarkers and immune signatures predictive of infection and disease outcome and thus contribute to improving clinical management, vaccine design and development of novel antiviral therapies against dengue.